Bottom Line:
There was a larger change in spring phenology in short-distance migrants than in long-distance migrants.Interestingly, the results further suggest that climate change has affected the phenology of short-distance migrants more in southern than in central Sweden.The results suggest that the much earlier calculated arrival to southern Sweden among short-distance migrants mirrors a change in location of wintering areas, hence, connecting migration phenology and wintering range shifts.

ABSTRACTMany migratory bird species have advanced their spring arrival during the latest decades, most probably due to climate change. However, studies on migratory phenology in the period before recent global warming are scarce. We have analyzed a historical dataset (1873-1917) of spring arrival to southern and central Sweden of 14 migratory bird species. In addition, we have used relative differences between historical and present-day observations (1984-2013) to evaluate the effect of latitude and migratory strategy on day of arrival over time. There was a larger change in spring phenology in short-distance migrants than in long-distance migrants. Interestingly, the results further suggest that climate change has affected the phenology of short-distance migrants more in southern than in central Sweden. The results suggest that the much earlier calculated arrival to southern Sweden among short-distance migrants mirrors a change in location of wintering areas, hence, connecting migration phenology and wintering range shifts.

Fig4: Mean (±SD) temperature for March, April, and May from the Swedish Meteorological and Hydrological Institute (SMHI) in southern (squares) and central Sweden (circles), respectively. Data are divided into historical data (1873–1917; open symbols) and present-day data (1984–2013; filled symbols)

Mentions:
Historical and present-day data on temperature for the six weather stations showed that spring temperature has increased between the historical and present day period. Due to low sample size, we could not analyze potential differences in the magnitude of temperature increase over time between southern and central Sweden, but in the six sampled sites average increase over time was larger in central than in southern Sweden for all spring months (south vs. central temperature increase: March: 1.3 vs. 1.8 °C, April: 1.4 vs. 1.9 °C and May: 1.4 vs. 1.7 °C (Table 2; Fig. 4).Table 2

Fig4: Mean (±SD) temperature for March, April, and May from the Swedish Meteorological and Hydrological Institute (SMHI) in southern (squares) and central Sweden (circles), respectively. Data are divided into historical data (1873–1917; open symbols) and present-day data (1984–2013; filled symbols)

Mentions:
Historical and present-day data on temperature for the six weather stations showed that spring temperature has increased between the historical and present day period. Due to low sample size, we could not analyze potential differences in the magnitude of temperature increase over time between southern and central Sweden, but in the six sampled sites average increase over time was larger in central than in southern Sweden for all spring months (south vs. central temperature increase: March: 1.3 vs. 1.8 °C, April: 1.4 vs. 1.9 °C and May: 1.4 vs. 1.7 °C (Table 2; Fig. 4).Table 2

Bottom Line:
There was a larger change in spring phenology in short-distance migrants than in long-distance migrants.Interestingly, the results further suggest that climate change has affected the phenology of short-distance migrants more in southern than in central Sweden.The results suggest that the much earlier calculated arrival to southern Sweden among short-distance migrants mirrors a change in location of wintering areas, hence, connecting migration phenology and wintering range shifts.

ABSTRACTMany migratory bird species have advanced their spring arrival during the latest decades, most probably due to climate change. However, studies on migratory phenology in the period before recent global warming are scarce. We have analyzed a historical dataset (1873-1917) of spring arrival to southern and central Sweden of 14 migratory bird species. In addition, we have used relative differences between historical and present-day observations (1984-2013) to evaluate the effect of latitude and migratory strategy on day of arrival over time. There was a larger change in spring phenology in short-distance migrants than in long-distance migrants. Interestingly, the results further suggest that climate change has affected the phenology of short-distance migrants more in southern than in central Sweden. The results suggest that the much earlier calculated arrival to southern Sweden among short-distance migrants mirrors a change in location of wintering areas, hence, connecting migration phenology and wintering range shifts.